Finding the Fourth Proportional to 2,662.58, 3,993.86 and 813.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,662.58 : 3,993.86 = 813.69 : x
2. Step 2: Convert to fraction form
   2,662.58/3,993.86 = 813.69/x
3. Step 3: Cross multiply
   2,662.58x = 3,993.86 × 813.69
4. Step 4: Simplify right side
   2,662.58x = 3,249,759.87
5. Step 5: Solve for x
   x = 3,249,759.87/2,662.58
6. Step 6: Final answer
   x = 1,220.53